PTV Vissim - Frequently Asked Questions (FAQs)

(#VIS29422)

I am using dynamic assignment for a network and output the convergence (*.cva) file after each convergence run. In this *.cva file, I see ShrConvPathTT and ShrConvEdgeTT. How are these calculated?

ShrConvPathTT is the share of the paths in percent that has met the convergence criterion if the convergence criterion 'Travel time on paths' has been selected. The percentage weighted by volume is specified in parentheses: Total volume (across all time intervals) of all converged paths / total volume of all paths used.

ShrConvEdgeTT is the share of the edges in percent that has met the convergence criterion if the convergence criterion 'Travel time of edges' has been selected. The percentage weighted by volume is specified in parentheses: Total volume (across all time intervals) of all converged paths / total volume of all paths used.

Note: A path is converged if the convergence criterion is met in all time intervals. From the *.cva file, you cannot recognize if the paths that converged in one time interval are the same that converged in another. However, you can open the Paths list in PTV Vissim (Traffic > Dynamic Assignment > Paths), and if you add the attribute Converged (Conv) to this list, then you can see if the path is converged or not.

For more information, click Help > PTV Vissim Help and refer to the section 'Saving data about the convergence of the dynamic assignment to a file'.